Kiln



Jan. 17, 1923. 1,656,642

H. G. LYKKEN KILN Filed April 15, 1925 3 Sheets-Sheet 1 Jan. 17, 1928.

1,656,642 H. G. LYKKEN KILN Fil d April 15, 1925 3 Sheets-Sheet 3 z 1 I l 1 I 2 72 28 1 i k /7 miauy fimfl Z Patented Jan. 17, 1928.

UNITED STATES PATENT OFF-ICE- HENRY G. LYKKEN, OF MINNEAPOLIS MINTTESOTA.

KILN.

Application filed A pril 15,1925. Serial No. 23,175.

The present invention relates to kilns for the burning of wares, such as clay wares and other like and similar products.

The invention comprehends, preferably, the down draft type of kiln wherein the burning medium passes downwardly through the ware located upon the floor of the kiln and then is exhausted or forced through suitableopenings in the floor and conducted through a duct or ducts leading from beneath such fioor.

Among the objects of the invention is to provide a fire box, preferably a single and sufficiently large fire box, in the kiln space and also preferably locating the fire box on from the fire box, may impinge against the roof, which is prefer: y crowned or domeshaped, and be deflected and distributed downwardly through the wars pile and around the outside of the fire box. The latter is preferably connected at one end or side thereof to an opening provided in the side wall of the kiln, through which opening the fuel may be introduced. Bythe use of a single fire box of the capacity for firing or burning the charge of Ware in the kiln, the combustion is more concentrated and a more efiicient, economical and easily controlled burning is effected than would be possible in a kiln having a series of bags or flashes distributed along the inner wall of the kiln. To distribute the fires in a large number of firing places in a furnace, is a wasteful and costly arrangement. A large excess of air usually required, in such case, to secure adequate combustion, thus entailing excessive dilation of the gases and large chimney losses. A strong draft is necessary to draw the required amount of air through the grates of the several firing places and the distribution of the gases or products of conibastion through the kiln is not uniform, owing to many conditions such as atmospheric conditions, as for example, where the wind or direction of flow of air against one side of the kiln operating some of the fires at a greater rate than those on the other side and even possibly causinga back draft of the fires on the opposite side. Moreover the maintenance of a plurality of fire boxes,

bags or flashes is more expensive and occupies greater floor space in the kiln than the present invention. Also, a larger amount of labor would be required for operating the device as well as greater cost of maintenance. i

The walls of toward the roof of the kiln and also to cut off direct rays or radiant energy,thus preventing a too rapid or intense heating of the ware, particularly the upper part of thepile or charge'in the kiln. I

Another object of the invention is to provide a kiln which is substantially gas tight so that the burning of the waremay be effected either under a pressure or a partial vacuum, the kiln, preferably, having means, such as. closableports or openings, prefer ably located in the lower part of the side walls of the kiln, as near the floor level,

whereby any number of said openings may' be opened for the controlling of the distribution of the hot gases in the kiln and the the fire box, of the present 1nvention, are such as to direct the gases;

stack of ware, and for the escape of the surplus or waste gases through such openings to the atmosphere, or, in the case of reduced pressure, theinlet of air through such openings, as desired. Glosable inspection open ings may also be provided in the sidewalls of the kiln as required or found desirable.

The invention also comprehendsthe preliminary heating and driving off of the moisture, usually termed water smoking before the effecting of theburning or firing.

Thismay be producedin one of several ways, such as the drawing of waste heat gases through the kiln and ware, in a reverse order or direction, thus effecting an economy of fuel; or the burning of the 151191, such as coal on a grate, which is preferably portable and removably locatedvin the fire box and thenremoved in the event of using other fuel devices for the firing or burning operation. If. the water smoking device he also used for firing or burning, such device may remain in place, the combustion being in creased to the firing or burning point. These devices, whether for water smoking or burning, comprehend the projection'and.

burning of powdered or pulverized fuel or atomized liquid fuel, or even gaseous fuels, in the fire box under suchcontrol as to effeet the desired water smoking or burning of the ware, this process being more rapid. The latter method is also preferable for the high firing or burning of the ware.

A further object of the invention is to use, in connection with the fire box, a portable fuel forced draft device, or fuel projecting means or device, such as an automatic stoker or a fuel pulverizer, atomizer, or the like, Which may operateto project the fuel into the fire box and also effect a pressure in the kiln during the burning of the were In this Way considerable saving in fuel, as well as in the labor connected with and the maintenance of the kiln is effected. A more uniform and'more easily controllable burning may be effected with less dependence upon natural draft or atmosphericconditions, and with a better distribution of the heat in the kiln than has been possible heretofore and in other kilns. With this method the firing or burning may be effected in considerably less time with a saving of about half of the time ordinarily required by previous methods.

The invention also comprehends the method or process of burning ware, such as clay ware and other like and similar materials or products, the process or method preferably involving the placing of, the ware in the kiln, the preliminary heating or water smoking of the ware and the firing or burning of the were by suitable products of combustion under given pressure.

The invention has other objects, capabilities and advantages as will later appear and are inherently possessed by the inven- Referring to the drawings showing a device for carrying out the invention, Figure 1 is a view in elevation of a kiln constructed in accordance with the invention; Figure 2 is a horizontal sectional view taken through ings, an illustrative embodiment of the invention is shown as comprising a kiln having a wall 1 of suitable material, lined with refractory material 2, a roof 3, also preferably of refractory material, and a floor 4 having therein suitable openings 5 communicating with one or more ducts 6 leading to a suitable stack and exhaust means, such as a fan, for

the conducting off of the waste gases after passing downwardly through the floor. The.

duct 6 may also be connected with suitable passages or conduits connected to other furnaces or kilns from which waste heat gases may be drawn in a reverse direction to the duct 6 into the kiln, as will be later more fully explained. While the particular form of kiln shown in the drawings is of the circular type, it is to be understood that other shapes may be used such as rectangular, or the like. At one side of the kiln the side walls 1 and 2 may have an opening or door 7 through which the ware to be burned, may be broughtinto or taken from the kiln, the door being preferably on the level with the floor 4.

Instead of a series or numberof bags or flashesin the kiln, a single fire box 8 is built within the kiln and upon the floor 4, such fire box being preferably elongated and having an end wall 9 and side walls 10 and 11 with the outer ends of the side walls formed integral with the walls 1 and 2, an opening 12 being preferably provided in the side wall of the kiln at the end of the fire box, as clearly shown in the drawings. The side walls 9, 10 and 11 extend upwardly a distance equal to or even greater than the height of the stack of the ware in the kiln and terminate at a suitable distance below the roof 3 so that the hot gases or products of con1- bustion will pass upwardly over the ends of thesewalls and against the roof 3 so as to be deflected downwardly thereby into the space of the kiln surrounding the fire box.

At suitable intervals in the side walls 1 and 2 and preferably near the floor level are provided a number of closable openings 13 communicating with the interior of the kiln. These openings are normally closed by a suit able closing means If and any niunber of them may be opened so as to permit the escape of the gases to the atmosphere and to effect the desired distribution of the gases in the kiln through the ware located therein. The side walls 1 and 2 of the kiln may also be provided with suitable inspection openings located at suitable points through which inspection of the interior of the kiln may be made, these openings being preferably also controlled by suitable closures.

The openings 7 and 12, during the burning operation, are closed or bricked up by suitable closing' means 16, 1.7 and 20, which with the other features above described, produces akiln which is substantially gas tight so that pressure may be effected in the kiln during the burning operation.

In starting the operation of the device. the ware usually taken into the kiln through the opening 7 and placed into a stack or pile 25 on the floor of the kiln. The opening 7 then "alled or. bricked in lQOTOFll] the closing means 16. The next step is the preliminary heating and drying of the were or the water smoking, as if is usually called. This may be effected in one of will later be more fully explained.

several ways. By one method, when the kiln is connected to the fines of other furnaces or kilns undergoing high fire or burning operations, an exhaust fan is located in the opening 12 soas to cause a draft or draw through the kiln and the duct 6 in the re-- effecting the burningoperation. This willbe explained more fully later.

A second operation of water smoking may be effected by the burning of coal or the like upon a portable grate 18 removably located on the floor 19 of the fire box 8, and the opening 12 provided with suitable closing means 17, 20 with an opening 21 for sufficient air draft to effect the combustion of the coal for the Water smoking operation. After the water smoking is effected the grate 18 and the wall portion 20 may then be removed, and the fuel device 22 for effecting the burning, may then be located in place, together with wall portion 20,112? r d 8 floor of the fire box may be covered with a suitable layer of cinders 23 as desired, and if ashesor other materials accumulate on the floor of the fire box, they may be withdrawn as desired. In lieu of this grate 18,

a portable automatic stoker 26 may be used, such a stoker being conventionally shown in Figures 5 and 6. This stoker may comprise a traveling or chain grate 27 suitably mounted in the stoker structure, a hopper 28"and a motor 29 suitably connected t6 operate the feed of the fuel from the hopper to the grate and effect a feed of the latter. The stoker structure may be carried upon wheels 30 for the moving of the stoker into and out of place in the chamberof the fire box as clearly shown in Figures 5 and 6 of the drawings. This device may remain in place, if desired, for the burning or firing of the ware, at which time the combustion of the fuel 011 the grate 27 may be increased by a forced draft to the ware burning or firing point, or the stoker may be Withdrawn and any of the other devices herein mentioned inserted to effect the burning or firing of the were. 1

A third method of water smoking may be effected by the use of a portable fuel device which may be in the form of a fuel pulverizer and blower 22 of any suitable type and construction, and having a discharge pipe 24 extending into the opening 21 for discharging powdered fuel into the fire box 8, as clearly shown in Figure 3 of the drawings. When set in place the rest of the opening 12 may be walled or bricked up to form a closing means 17, 20, as clearly shown in Figure 3 of the drawings. The

powdered fuel may burn under controllable conditionsso as to effect thewater smoking step of the process, and when this is completed, the fuel device 22 may then be oper: ated at a greater speed or the like so as to effect a hotter combustion of the fuel for the firing. a

If any of the previous methods be used for water smoking, the firing may thenflbe effected by the use of either of the fuel devices- 22 or 26 located inplace as above forced draft, undergoes the combustion 1n;

the fire box 8 sufficiently to produce hot products of combustion under pressure so the same may blow upwardly against the roof of: the kiln and then distributed down wardly through the stack of the Ware and thence through the openings in the floor el of thekiln and conducted off through the duct .6 to the chimney or smoke stack. Should it be desired'to effect a greater dis tribution of gases at one part of the'kiln than at another, thismay be produced by opening certain of the holes or openings 13 to permit the escape of the gases therethrough to the atmosphere.- This will effect a reduction of pressure in that part of the kilnwhere the openings 13 are opened so that a more rapidpassing of the hot gases of combustion to the portion of the stack in that part of the kiln and effect a greater burning thereof. Inasmuch as the kiln is normally substantiallygas tight, the burning of the ware may be effected under a positive pressure of gaseswith the resultant gain in time of burning and less loss of heat. If, however, it be desired to effect the; burning under an exhausted or partial vacu um condition, a suction blower may be con nected totheductfi so as to draw the'prodnets of combustion through the blower and from the kiln at a greater rate than the combustion in the fire box 8 is being effected and thusproduce the desired partial vacuum in the kiln and in the ware.

By the use of a single fire box of large capacity a perfect heat distribution in a down draft kiln is effected. The fire box is also designed so as to protect the ware from the direct heat or radiant energy of the flames in the fire box and to conduct the hot gases of combustion to a deflecting surface, such as the roof, for the distribution of the hot gases through the ware in a substantially uniform manner. The difference in density of the gases, due to the variatlon 1n temperature will cause them to stratify and distribute uniformly throughout the kiln. This is aided by the hot gases ascending from the fire box and spreading under the roof or crown of the kiln, thus continually forcing the relatively cooler gases downwardly and finally through the openings of the floor. The fire box is preferably built on top of the floor and with a ,floorof its own so as to close off the fire box from communication to the openings of the floor, thus making that part of the floor gas tight with reference to the fire box.

While I have herein described the use of the device 22 as for projecting powdered or pulverized fuel, it is to be understood that this device may be of the liquid fuel type supplying atomized or sprayed liquid fuel into the fire box 8 or the device may be of the type for supplying a gas or mixture of gases for efiecting the desired combustion in the firebox. is a a Having thus described my invention, I claim; it

1. A kiln comprising a floor upon which the ware to be burned is placed, side walls and a, roof, means for supplying products of combustion under pressure to said ware, said side walls having closable openings located therein above said floor for permittingcontrollable escape of gases to the atmosphere.

2. A kiln for burning clay wares having substantially gas tight walls and a roof, comprising a perforated floor underlaid with a duct for carrying away the products of combustion, and a fire box over said floor, said walls having a plurality of regulatable ports about the periphery of the kiln and above the floor line for regulating the escape of gases to the atmosphere. g y i 3. A kiln comprising a single fire box built on the floor of the kiln and extending into the kiln and approximately to the height of the Ware to be burned. V a 4. A kiln comprisinga floor, ducts below the floor for conducting gases, a single fire box built on the floor of the kiln and free of the ducts, said fire box extending inward from an opening provided in the kiln.

5. A kiln comprising a floor having open ings for the passage of hot gases, a fire box on the floor of the kiln and extending into said kiln from an opening provided in a side wall ofthe kiln and means for rojecting powdered coal into said fire ox whereby the powdered coal burns in said fire box.

a 6. A kiln comprising a floor, a side wall and a roof, a single fire box over the floor extending into the kiln from an opening in the side wall, said fire box having surrounding walls extendin upwardly for protecting the ware from radiation from the lire box and for conducting products of combustion to the roof. a

7. A method of treating ware in a kiln comprising drawing gases upwardly through the floor of the kiln through the ware and into the atmosphere for water smoking for a predetermined period of time, and afterwards forcing products of combustion from a fire box downwardly through said ware through the floor of the kiln for burning the wares. 8. A kiln comprising a floor, a dome shaped roof, side walls, and a single fire box above said floor extending into said kiln beneath said roof.

9. A kiln comprising a floor, a dome shaped roof, side walls, and a single fire box above said floor extending into said kiln beneath said roof, a wall of said lire box extending upwardly approximately to the height of the Ware to be burned. y

10. A kiln comprising a floor, a dome shaped roof, side walls, and a single fire box above said floor extending into said kiln beneath said roof, said side walls having regulatable ports for controlling the escape of hot gases and for regulating the distribution of the flow of said gases. o

11. A kiln comprising a floor, a dome shaped roof, side walls, and a single fire box above said floor extending into said kiln beneath said roof, and ducts underneath said floor for withdrawing gases from said kiln, and means for distributing the flow of gases within said kiln.

12. A kiln comprising a floor, a dome shaped roof, side walls, a single fire box above said floor extending into said kiln beneath said roof, ducts underneath said floor for withdrawing gases from said kiln, said side walls having regulatable ports for controlling the distribution of the flow of gases within said kiln. a

In witness whereof, I hereunto subscribe my name to this specification.

HENRY G. LYKKEN. 

